The problem with the ansible is that (if I'm remembering my quantum right: It's been 2 years since graduate quantum), when you entangle to particles-measuring one causes the *wave function* of the other to collapse: but you cannot control *how* it does so. (That is, I can measure an entangled particle and go "aha! This one has momentum X.. sot he other must have momentum -X, and its wave function has now collapsed! But I cannot go "I will ADD momentum X to my particle, causing the other to have momentum -X!")

Now, you might go "Wait! But if we can choose to collapse some wave functions, but not others, we could still use that as the basis for sending ones and zeroes!"But, again, that doesn't quite work: because (again, I'm pretty sure I'm remembering this right), you cannot measure to see if the waveform has collapsed yet. . I *think*. I definately recall a lecture explaining why the ansible couldn't work, but I admit I may be getting the details a bit wrong. =/.

I have a hard time beliving that Chinese scientists are making breakthroughs in quantum teleportation. This is a country that has to steal factory blueprints... either that or this whole quantum teleportation thing is not nearly as complicated as they are letting us believe...

/ not the biggest sci-fi/fantasy reader// just started Revelation Space because some farker recommended it and so far it's a pretty fun read, thanks to whoever/// just saw lighthuggers referenced somewhere else on fark today

I've read a few books from the Revelation Space series, finishing the rest is on my to-do list. It's the second best series I've read so far. The Commonwealth series by Peter Hamilton is the best: Pandora's Star, Judas Unchained, The Dreaming Void, The Temporal Void, and The Evolutionary Void.

I like both those guys and both series are great. Just wrapped Reynolds' Terminal World a few weeks back. Good read.

Heron:It isn't like the matter in your body is proprietary or anything; at an atomic and quantum level, your physical self cycles through with "new" matter every week or so. Discrete macro-matterforms (I just made that up because it sounded funny) are more like a pattern in space than a locked relationship between specific instances of matter. As such, teleportation doesn't really present the problem you describe here. You're already becoming a "new person" in a material sense on a regular basis; teleportation -assuming ~100% pattern fidelity- would just accomplish the process faster while transporting you to a different location in the process.

Coincidentally, this is also why the worry about being transported into something isn't much of a concern(for you at least); you'd be reassembled out of the ambient matter at the location.

Yes, but that replacement happens gradually so there is no discontinuity of your sense of self, whereas every cell in your body being ripped apart and the reconstituted somewhere else would cause your sense of self to be destroyed just as surely as if you died. It's like the situation of upgrading to a robot body. If you just copy your mind to a fully robotic body, the original you will still grow old and die and enjoy none of the benefits of the functionally immortal robot you. If you upgrade yourself in the "boiling frog" method of upgrading instead, and slowly replace small parts of your body and brain with cybernetic upgrades, you'll have a continuous sense of selfhood even though the end result is the same, a human mind in a robot brain and body.

VonKraut:Jument: Sadly yeah, teleportation is almost certainly completely impossible. To reconstitute a brain you would have to reconstitute not only the cells but electrical charges and stuff. I hate to say never but it's never going to happen. You could jump through a wormhole or pop into hyperspace, of course. Much easier than true teleportation.

Who knows? We are just in the begging of this technology, these kinds of statements have a way of coming back and biting you like, "Guitar bands are on the way out" or "There is no reason anyone would want a computer in their home" Just because we can't conceive of it now doesn't mean it won't happen, or that we shouldn't try.

We still don't even have flying cars and you think it's possible that we could rewrite physics *and* overcome the insurance obstacles involved in teleportation? It'll never happen.

Jument:Sadly yeah, teleportation is almost certainly completely impossible. To reconstitute a brain you would have to reconstitute not only the cells but electrical charges and stuff. I hate to say never but it's never going to happen. You could jump through a wormhole or pop into hyperspace, of course. Much easier than true teleportation.

That's why you have to be asleep to take a jaunt. If you're awake you go raving mad.

It will take too long to explain. Let me sum up - you're probably typing something that the web server interprets as markup language, and deletes so it doesn't get tricked.

I was basically wondering whether someone could explain the difference between quantum coupling and quantum teleportation. In plain English. Seems to me like quantum coupling over 143 km would be far more useful and impressive, but maybe there's a reason why the coupling either isn't useful or isn't possible.

belhade:Jument: Sadly yeah, teleportation is almost certainly completely impossible. To reconstitute a brain you would have to reconstitute not only the cells but electrical charges and stuff. I hate to say never but it's never going to happen. You could jump through a wormhole or pop into hyperspace, of course. Much easier than true teleportation.

That's why you have to be asleep to take a jaunt. If you're awake you go raving mad.

Fano:belhade: Jument: Sadly yeah, teleportation is almost certainly completely impossible. To reconstitute a brain you would have to reconstitute not only the cells but electrical charges and stuff. I hate to say never but it's never going to happen. You could jump through a wormhole or pop into hyperspace, of course. Much easier than true teleportation.

That's why you have to be asleep to take a jaunt. If you're awake you go raving mad.

mojotele:rkettens: If you look into it you'll find that the vacuum of space is a few degrees above absolute zero, they used that fact to help pinpoint the big bang.

This. Back when I was doing experiments on infrared detectors for the James Webb telescope we had to take the detectors down to 32 Kelvin to mimic the environment of space (and also to see anything). That's damn cold, but not absolute zero.

As you go further out from the solar system things obviously get colder, but you still never hit absolute zero due to cosmic radiation.

Yeah, here's the thing. If something ever did hit absolute zero, it would "stop." I am not sure that would be good for the fabric of space time.

Fano:belhade: Jument: Sadly yeah, teleportation is almost certainly completely impossible. To reconstitute a brain you would have to reconstitute not only the cells but electrical charges and stuff. I hate to say never but it's never going to happen. You could jump through a wormhole or pop into hyperspace, of course. Much easier than true teleportation.

That's why you have to be asleep to take a jaunt. If you're awake you go raving mad.

100 years ago, Quantum theory was not even conceived of. About 50 years ago Star Trek was conceived but considered total fantasy. Some of Star Trek fantasy is now common today for real. Never say no or impossible if minds can conceive of it. We only think we know a lot but have no conception of what we don't.

Ika7734:What I found as a "well then what's the point" is FTFA:"In an active feed-forward protocol, conventional data is sent alongside the quantum information, enabling the recipient to decipher the transferred signal with a higher efficiency."

Does that mean there's also a standard type of transmission in parallel? If so, then why bother with the quantum action at a distance for the transmission.?

Because it still enables secure communications. You can *always* tell if a quantum signal has been intercepted or "peeked" at.

Not really. Heisenberg's uncertainty principle says that you can't know both the position and momentum of a particle (say, an electron) to an arbitrary degree of precision, but the effect is not generally large enough to make much of a difference once you move up past the atomic scale. Even in the minutae involved in physical chemistry, where you're dealing with individual atoms, you're not really concerned about precisely where every electron is or how fast it is going, you only are interested in the aggregate behavior of each atom and how it contributes to the behavior of the molecule.

Somaticasual:Either that, or you're reassembling someone who's going to be immediately at absolute zero (from a lack of molecular movement, because if you can find the position you can't find the momentum, therefore everything assembles at zero motion)?

That's not quite how it works. Even if you could perform a position measurement precisely enough that you have zero information about the momentum (impossible in actuality), it doesn't imply that the object's momentum is actually zero -- it only means that you don't know anything about its momentum.

In fact if you'll notice, in your scenario you are actually able to precisely determine both the position (which we've found to an arbitrary degree of precision) and the momentum (which, apparently because we weren't able to measure it, is now exactly zero) of a particle. This violates not only Heisenberg's Uncertainty Principle, but also the Laws of Conservation of Energy and Momentum. After all, where did all the momentum and kinetic energy of the particle go when its momentum suddenly became zero?

Also, nothing is ever at absolute zero. Atoms and molecules always move at least a little.

jimw:100 years ago, Quantum theory was not even conceived of. About 50 years ago Star Trek was conceived but considered total fantasy. Some of Star Trek fantasy is now common today for real. Never say no or impossible if minds can conceive of it. We only think we know a lot but have no conception of what we don't.

I really expected that to turn into a "and that's why the bible could do the same thing" post. Whew, close one.

Of course the most disturbing part is the question of what happens from your point of view when you get transported. You'd think that from your POV, you die instantly as you are torn apart on a atomic level and that the person that is reconstituted on the other end only think they are you because they have all of your memories. There'd just be no way to know what happens from a person's perspective.

I don't know if anyone mentioned this, but it's shown in Star Trek that there is something equivalent to a unique consciousness/soul, for lack of a better word, which is transmitted in teleportation.However, it's also shown that entirely independent clones can be created through the teleporter.

Gleeman:Mad_Radhu: Of course the most disturbing part is the question of what happens from your point of view when you get transported. You'd think that from your POV, you die instantly as you are torn apart on a atomic level and that the person that is reconstituted on the other end only think they are you because they have all of your memories. There'd just be no way to know what happens from a person's perspective.

Gawdzila:That's not quite how it works. Even if you could perform a position measurement precisely enough that you have zero information about the momentum (impossible in actuality), it doesn't imply that the object's momentum is actually zero -- it only means that you don't know anything about its momentum.

Actually, my point there was that you couldn't replicate it on the other end since you hadn't measured it (the momentum), so the "recreated" version of you on the other end might have no molecular movement. Granted, that does bring about a larger question - assuming you can reassemble something in the first place, how do you impart motion when it's being reassembled?